Prematurity. Babies born before 37 weeks (premature babies have more fragile bodies and may be more easily injured).

Cephalopelvic disproportion. The size and shape of the mother's pelvis is not adequate for the baby to be born vaginally.

Dystocia. Difficult labor or childbirth.

Prolonged labor

Abnormal birthing presentation. An example of this is a buttocks first (breech) delivery.

Maternal obesity

What are some of the more common birth injuries?

The following are common birth injuries:

Brachial palsy. This occurs when the group of nerves that supplies the arms and hands (brachial plexus) is injured. It is most common when there is difficulty delivering the baby's shoulder, called shoulder dystocia. The baby loses the ability to flex and rotate the arm. If the injury caused bruising and swelling around the nerves, movement should return within a few months. Tearing of the nerve may cause permanent nerve damage. Special exercises are used to help maintain the arm’s range of motion while healing occurs.

Bruising or forceps marks. Some babies may show signs of bruising on the face or head simply because of the trauma of passing though the birth canal and contact with the mother's pelvic bones and tissues. Forceps used with delivery can leave temporary marks or bruises on the baby's face and head. Babies delivered by vacuum extraction may have some scalp bruising or a scalp cut (laceration).

Caput succedaneum. Caput is a significant swelling of the soft tissues of the baby's scalp. This develops as the baby travels through the birth canal. Some babies have some bruising of the area. The swelling usually goes away in a few days without problems. Babies delivered by vacuum extraction are more likely to have this condition.

Cephalohematoma. This is an area of bleeding between the bone and its fibrous covering. It often appears several hours after birth as a raised lump on the baby's head. Over time, the body reabsorbs the blood. Depending on the size, most cephalohematomas take 2 weeks to 3 months to disappear completely. If the area of bleeding is large, some babies may develop jaundice as the red blood cells break down.

Facial paralysis. During labor or birth, pressure on a baby's face may injure the facial nerve. This may also occur when forceps are used for delivery. The injury is often seen when the baby cries. There is no movement on the side of the face with the injury and the eye can’t be closed. If the nerve was only bruised, the paralysis usually improves in a few weeks. If the nerve was torn, surgery may be needed.

Fractures. Fracture of the clavicle or collarbone is the most common fracture during labor and delivery. The clavicle may break when there is difficulty delivering the baby's shoulder or during a breech delivery. A baby with a fractured clavicle rarely moves the arm on the side of the break. However, healing occurs quickly. As new bone forms, a firm lump on the clavicle often develops in the first 10 days. If the fracture is painful, limiting movement of the arm and shoulder with a soft bandage or splint may be helpful.

Subconjunctival hemorrhage. This is the breakage of small blood vessels in the eyes of a baby. One or both of the eyes may have a bright red band in the white part of the eye. This is very common and does not cause eye damage. The redness is usually absorbed in a week to 10 days.